1. Field of the Invention
The present invention relates generally to floor cleaning devices.
2. Description of Related Art
Many different types of floor cleaning devices are commonly used to clean carpets, rugs and bare floors. Examples of such devices include wet extractors, vacuum cleaners, floor polishers, steam cleaners and the like. A traditional upright floor cleaning device has a base assembly and an operating handle that extends upwardly from the rear of the base assembly. The operating handle is used to guide the base assembly across the floor during operation, and in operation the handle is pushed forward, causing the base to move forward and the handle to pivot downward, and pulled back, causing the handle to move up and the base to move backwards. The operating handle is frequently designed to incorporate various parts of the cleaning device, such as water tanks, vacuum motors, filters, and the like. In these configurations, much of the device's weight is moved up to the handle, thus requiring the user to bear a portion of this weight when operating the device, particularly on the forward strokes. The operating handle also may be equipped with accessory cleaning tools and an extension hose for remote cleaning.
The operating handle of conventional cleaning devices is not configured to facilitate compact storage, shipping, and/or transportation of the device. Specifically, when the floor cleaning device is not in use, most users desire to store the device in a closet or other small space. Because the operating handle occupies a relatively large amount of space, its design is not ideal for compact storage. Shipping is also problematic with conventional cleaning devices because their bulky shapes can not be fit into conventional rectangular shipping boxes without including a large amount of unused air space in the box, which increases shipping cost. In order to reduce this additional shipping expense, some manufacturers disassemble the devices for shipment. While such disassembly reduces shipping costs, it is less desirable to customers, who typically prefer not to assemble the devices, may not be able to do so, and may find it inconvenient to disassemble the device for later storage, shipment and/or transportation. Also, when the floor cleaning device must be transported from one location to another (e.g., up or down a flight of stairs), a user must lift the device off the floor by the operating handle and carry the device in a relatively awkward position to the new location. It can be appreciated that the bulky nature of the device makes this an undesirable task for many users. Similarly, transporting the floor cleaning device in a vehicle (e.g., in a trunk compartment) can be challenging for many users due to the difficulties in loading and unloading the device into and out of the vehicle. This challenge is compounded by the fact that, in the case of wet extractors, users may wish to avoid tipping the device on its side to prevent water from escaping into the vehicle.
In an effort to overcome these problems, floor cleaning devices have been designed in which the operating handle can be partially collapsed to facilitate storage, shipping, and/or transportation of the device. For example, one floor cleaning device has been designed in which the operating handle includes an upper fork and a lower fork, wherein the upper fork can be folded downwardly to a position adjacent the lower fork. An example of such a device is shown in U.S. Pat. No. 3,673,628 to Gaudry et al. (This patent and all others discussed in the present disclosure are hereby incorporated herein by reference in their entireties.) While this device is an improvement on traditional devices, the operating handle is only partially collapsible and thus continues to occupy too much vertical space.
Another floor cleaning device has been designed in which the operating handle includes a pair of upper arms and a pair of lower arms, wherein the lower arms can be pivoted downwardly relative to the base assembly and then the upper arms can be slid inwardly alongside the lower arms. An example of such a device is shown in U.S. Pat. No. 4,245,371 to Satterfield. While the collapsed operating handle of this device occupies a smaller amount of vertical space, a portion of the operating handle still extends laterally a considerable distance from the base assembly and thus occupies a larger amount of horizontal space. As such, this design in not ideal for compact storage, shipping, and/or transportation of the device.
Yet other floor cleaning devices have been designed in which the operating handle includes an upper portion and a lower portion, wherein the upper portion can be folded downwardly relative to the lower portion and then the folded upper/lower portions can be pivoted downwardly relative to the base assembly. Examples of such devices are shown in U.S. Pat. No. 3,203,707 to Anderson and U.S. Pat. No. 3,204,272 to Greene et al. While the collapsed operating handles of these devices occupy a smaller amount of vertical space, substantial portions of the operating handles extend laterally from the base assemblies and thus occupy an even larger amount of horizontal space. As such, these designs are not suitable for compact storage, shipping, and/or transportation of the devices.
Still other floor cleaning devices have been designed in which the operating handle extends upwardly from a two-part base assembly (which includes a horizontal portion and a vertical portion), wherein the vertical portion of the base assembly can be pivoted downwardly onto the floor and then the operating handle can be folded onto the two-part base assembly. Examples of such devices are shown in U.S. Pat. No. 4,660,246 to Duncan et al, U.S. Pat. No. 4,662,026 to Sumerau et al., U.S. Pat. No. 4,670,937 to Sumerau et al., U.S. Pat. No. 4,763,382 to Sumerau, and U.S. Pat. No. Des. 310,438 to Burns. While these devices also occupy less vertical space, the collapsed base assembly occupies an even larger amount of horizontal space. Thus, these designs are also not suitable for compact storage, shipping, and/or transportation of the devices. Furthermore, such devices require the operator to actually remove the handle, reverse it, and reinsert it into the device, which is inconvenient for the operator. This design also limits the manufacturer's ability to place electric switches in the handle, which also inconveniences the operator.
A variety of wet extraction cleaning devices are available for cleaning carpets and bare floors. Typical wet extractors have a supply tank for storing cleaning fluid, and a fluid deposition system that is used to deposit the cleaning fluid onto the floor. In some cases, a mixture of water and detergent may be placed in the supply tank, but in other cases, the wet extractor has a separate detergent tank, and fresh water is placed in the supply tank and is mixed with detergent from the detergent tank by the fluid deposition system. Typical wet extractors also have a vacuum source that is used to suck in the deposited cleaning fluid, and any dirt or grime that it extracts from the floor, through a floor nozzle. This waste fluid is deposited and stored in a recovery tank.
In order to prevent waste fluid from entering and possibly damaging the vacuum source, the recovery tank is positioned, in a fluid flow sense, between the vacuum source and the floor nozzle. The recovery tank is designed to remove the waste fluid from the air flow in which it is entrained, while allowing the air to continue to the vacuum source. Typical wet extractors also have a shutoff mechanism that blocks the vacuum source when the recovery tank is full and prevents waste fluid in the recovery tank from sloshing into the vacuum source when the wet extractor is moved back and forth by the operator. This shutoff mechanism is usually provided in the form of a float device. The float device has a buoyant float that rises on the water, and a sealing surface on or attached to the buoyant float that blocks the passage to the vacuum source. In many cases, the operator of the wet extractor will be alerted to the fullness of the recovery tank by the change in pitch of the vacuum source as its air flow is becoming cut off, and this serves as a signal to empty the recovery tank.
Although a number of different wet extractors, supply tanks and recovery tanks have been produced, the prior art suffers from numerous shortcomings. One shortcoming of prior wet extractors is the that the inlet nozzle often becomes coated or clogged by dirt and debris removed from the surface being cleaned. This is especially true where the inlet nozzle is provided as a narrow slit, which is a common and favorable configuration to generate high-speed airflow and strong, focused suction to remove the fluid and dirt. Because the nozzle profile is so narrow, it is difficult to clean using conventional means, and users must resort to cleaning the nozzle with pipe cleaners and other specialized devices.
Another shortcoming of the prior art relates to supply tanks, which are typically difficult to fill unless a large sink or hose is available. For example, U.S. Pat. No. 5,406,673 to Bradd et al. (the '673 patent) and U.S. Pat. No. 5,937,475 to Kasen et al. (the '475 patent) provide supply tanks that are approximately bucket-shaped, and require a large vertical clearance to place them under sink faucet outlets. Furthermore, such a design may be difficult to fill unless the faucet can be swiveled out of the way to place the tank into the sink. Still further, the supply tank of the '475 patent is retained in place by latching devices that must be manipulated before removing the supply tank. Such latches require additional manufacturing, are subject to breaking, are often not intuitively understood by users, making them difficult to operate, unhook and realign for reinstallation. Similar problems are present with the supply tank of U.S. Pat. No. 6,073,300 to Zahuranec et al. (the '300 patent).
Other shortcomings of the prior art relate to the design of the recovery tank. For example, the recovery tank disclosed in the '673 patent has a complex multi-chambered design that requires the incoming air/fluid mixture to traverse a horizontal inlet that can easily backflow when the vacuum source is turned off, causing waste fluid to seep back out onto the floor. The recovery tank of the '673 patent is also inconveniently placed below the supply tank, and an operator must tilt the operating handle back and away from the upright resting position in order to access the recovery tank. Such maneuvering is awkward to perform and risks toppling the device during recovery tank removal and insertion. Still another shortcoming of the '673 device is that the recovery tank float is located in a relatively large chamber, making it more subject to fluid sloshing and unnecessary vacuum cut-off. The complex structure of the '673 recovery tank also requires disassembly to drain, and is relatively expensive to manufacture.
The recovery tank of the '475 patent also suffers from shortcomings. One shortcoming is that the fluid inlet leads almost directly into the main reservoir of the water recovery tank, and allows the incoming air/fluid mixture to short-circuit the reservoir and go directly into the outlet leading to the vacuum source. Another shortcoming of the '475 recovery tank is that it requires a complex multi-piece construction in which the float is permanently sealed, increasing the cost of construction, making it difficult or impossible to service the float, and necessitating the inclusion of a separate drain plug. Also, like the '673 device, the '475 recovery tank is retained in the wet extractor under the supply tank, and the operating handle must be tilted back from the upright resting position to remove the recovery tank. Still further, the '475 recovery tank uses a pivoting tank handle, which requires additional material and construction effort, and is susceptible to breaking. The recovery tank of the '300 patent has similar shortcomings. In addition to being a complex multi-piece structure, the '300 recovery tank is retained by a latch that requires additional material and construction effort, may be difficult to operate, and appears to be operable only when the operating handle is leaned back from the upright resting position. Other prior art recovery tanks suffer from these and other problems.
Other shortcomings of the prior art relate to the overall configuration of the supply and recovery tanks in the wet extractor. In many instances, such as in the '673 patent, the '475 patent and the '300 patent, the supply tank is carried in the operating handle of the device. Such devices suffer from being difficult to ship and store. These configurations are also unduly complex, making them expensive to manufacture and difficult to operate. Still further, such devices require more operator effort because the operator must bear the weight of the heavier operating handle when the wet extractor is at the end of the forward stroke and the handle is tilted at its lowest angle relative to the ground. Other devices, such as the wet extractor disclosed in U.S. Pat. No. 6,131,237 to Kasper et al. (the '237 patent), have reduced the weight of the operating handle by placing both the supply and recovery tanks in the base, but in the '237 patent device, the handle weight is increased by mounting an accessory device to it, and the operating handle still must be reclined away from the upright resting position to remove the tanks. Furthermore, the supply and recovery tanks of the '237 patent are contained in a single complex chamber having a flexible bladder, which is relatively difficult to manufacture, operate and clean.
Numerous fluid systems for extractors have been developed that apply fluids to a surface to be cleaned to help clean stubborn stains and extract deeply-rooted dirt and grime. The fluid may simply be water, or it may include detergents, fabric brighteners, perfumes and other useful compounds. The fluid also may be heated or converted to steam before being deposited. Liquid management is a continuing challenge in the design of wet extractors. In order to operate well, the operator of the wet extractor must be provided with some way of controlling when the fluid is deposited onto the floor or other surface being cleaned. Furthermore, such operations should be performed for both floor operations, and, if an auxiliary tool attachment is provided, for remote operations.
Previous attempts to provide liquid management systems have entailed the use of complex, bulky and costly arrangements of pumps, valves, solenoids, switches and the like. For example, U.S. Pat. Nos. 6,286,180 (the '180 patent) and 6,131,237 (the '237 patent), both to Kasper et al., disclose decentralized liquid management systems that require the pump priming assembly to be connected to a vacuum source to prime the pump. This requires additional construction material and limits flexibility in locating the priming assembly. This also may cause some delay between the time the pump is activated and the time that fluid is pressurized and available for depositing on the surface to be cleaned. As such, these systems require the fluid pump to operate at all times, and must use a mechanical pushbutton-type valve to control the flow of fluid. The use of this mechanical valve requires the valve to be located in the handle of the device so that it can be operated by the user. Furthermore, alternatives to mechanical valves in systems such as those in the '180 and '237 patents typically require the use of expensive electrically-operated solenoid valves to control fluid flow, such as shown in U.S. Pat. No. 6,513,188 to Zahuranec et al. (the '188 patent). A similar deficiency is encountered in the gravity-fed systems of U.S. Pat. No. 6,073,300 to Zahuranec et al. (the '300 patent), and U.S. Pat. No. 5,676,405 to Reed (the '405 patent), which also require a mechanical valve that must be positioned in the handle of the device, or, if the valve is positioned outside the handle, an expensive solenoid to operate the valve.
Another deficiency of prior art liquid management systems relates to the manner in which such systems are converted to operate in an accessory tool mode. In typical prior art systems, such as those disclosed in the '300 patent, the '180 patent, and the '405 patent, the accessory tool is installed in at least two steps. In one step, the vacuum hose for the accessory tool is installed, and in the other step the fluid line to the accessory tool is attached. In many cases, such as in the '405 and '300 patents, the fluid hose hookup is also constructed as a complex and relatively expensive fitting that has a shutoff valve integrally formed with the fluid passage at the point of connection. These systems are inconvenient and relatively difficult to use.
Other prior art accessory tool hookup systems have been developed that use a single plug to install both the vacuum source and the fluid line. Examples of such devices are provided in U.S. Pat. No. 5,400,462 to Amoretti (the '462 patent), U.S. Pat. No. 5,459,901 to Blase et al., (the '901 patent), and U.S. Pat. No. 5,669,098 to Tono (the '098 patent). Although these devices conveniently use a single plug to attach the tool to a vacuum source and a fluid source, neither the '462 patent nor the '901 patent provides any way to divert vacuum and fluid flow from a floor-cleaning circuit to the accessory tool circuit. Both of these devices also pose electrical shock risks to the user due to the exposed electrical switch and terminals in the '462 patent, and the use of a separate electrical plug in the '901 patent. This risk is compounded by the lack of any sort of shutoff valve or anti-siphoning device for the fluid lines at or near the connection point. The '098 patent also suffers from deficiencies as it relies on a coaxial design that is unnecessarily complex, and uses a complex shutoff valve that is integrally formed with the fluid passage at the point of connection with the accessory tool. Such combined fluid passage/shutoff valves can be relatively expensive, and, because the valve is necessarily positioned at the point of contact between the parts, the valves are susceptible to being contaminated by dirt and debris on the parts, which may impair the seal and result in leakage.
Other deficiencies of prior art liquid management systems relate to detergent mixing and metering systems. It many instances, wet extractors have been provided with separate clean water and detergent tanks so that the user does not have to mix the fluids into a single tank. The use of separate clean water and detergent tanks also allows the user to adjust the amount of detergent that is mixed with the water. Previous detergent control valves have been unduly complex. For example, the control valve disclosed in U.S. Pat. No. 4,570,856 to Groth et al. (the '856 patent) uses a complex system of hoses to pressurize the detergent chamber, and uses a rocker assembly to selectively pinch off the detergent supply hose, which can damage the hose and require more expensive hose material. Other systems, such as the system in U.S. Pat. No. 5,937,475 to Kasen et al. (the '475 patent), use valve assemblies that are located in the clean water flow path, and require a rotational movement to actuate. such devices allow clean water and detergent to mix even when the device is inactive, and must be turned by hand to change the detergent mixture setting.
It is well known in the art of cleaning floors and other surfaces that it is often desirable to agitate the surface being cleaned to shake out and extract deeply embedded dirt and grime. As such, various different mechanical agitators have been made to agitate floors and carpets to assist with cleaning operations. These devices have been used on their own, in conjunction with vacuums and wet extractors and with other cleaning devices. Many previously known agitators can generally be placed into various categories, such as horizontal rotating brushes (often called “beater brushes” or “disturbulators”), and vertical rotating brushes, but other types of agitator have also been devised.
One type of agitator, the horizontal rotating brush, is exemplified by the device disclosed in U.S. Pat. No. 5,937,475 to Kasen et al. (the '475 patent). In this design, the brush comprises an elongated spindle that is oriented horizontally with its rotating axis parallel to the surface to be cleaned, and has a number of bristles extending radially from its surface. When the spindle is rotated, the bristles are driven downward into the surface being cleaned and swept back through a circular arc. Although these devices have been used with some success, it has been found that they suffer from some disadvantages. For example, they tend to spray fluids deposited by wet extractors, they accumulate dirt (especially hair) and require constant cleaning and attention, and are subject to bearing and drive belt failure. In addition, the aggressive sweeping of the bristles through the carpet or other surface being cleaned tends to cause accelerated wear of the surface, and may be unsuitable for delicate fabrics.
A second type of agitator, the vertical rotating brush, is exemplified by U.S. Pat. No. 6,009,593 to Crouser et al. (the '593 patent). This type of agitator comprises one or more spindles that rotate about an axis aligned orthogonally to the surface being cleaned. Each brush has a number of bristles that project approximately along the axis of rotation, and are swept through a flat circular path (relative to the device) when the brushes rotate. Like the horizontal rotating brush design, this design is prone to accumulating dirt, and particularly hair. Furthermore, it has been found that the counter-rotating vertical brushes of this agitator tend to leave an undesirable streaked pattern in the nap of some carpets, and, when used in a wet extractor, tend to leave corresponding streaks of unrecovered fluid on the surface being cleaned. The aggressive sweeping of the bristles through a large path of travel is also believed to contribute to accelerated carpet wear and may be unsuitable for delicate fabrics.
Another type of agitator that has been devised uses a brush that is simultaneously vibrated laterally relative to the fore-aft direction of the cleaning device and vertically relative to the plane of the surface being cleaned. Such devices are shown in U.S. Pat. Nos. 2,109,621 to Kirby (the '621 patent) and 6,353,964 to Andrisin, Jr. et al. (the '964 patent). The '621 patent uses a turbine to drive a shaft that has a brush at its end and an eccentric weight between the brush and the turbine. As the shaft rotates, the eccentric weight applies both vertical and lateral centripetal forces to thereby impel the brush with a “rapid scratching movement.” Additional vertical forces against the surface being cleaned are applied by a set of springs mounted between the brush and the device's housing. The '964 patent uses a similar arrangement, but instead drives the brush using an eccentric that rotates in a corresponding hole in the brush. The eccentric rotates about an axis that is angled relative to the floor, and thereby imparts lateral, longitudinal and vertical forces and movements to the brush. Both of these agitators apply a significant vertical force to the brush, which is believed to contribute to accelerated wear of the surface being cleaned and tends to pound dirt and debris more deeply into the surface being cleaned. These agitators (especially the '621 patent) are also believed to provide inconsistent cleaning due to the somewhat random movements generated by their drive systems. Furthermore, these agitators are somewhat limited in their application because they rely on turbine drives that can not be operated independently of the vacuum source.
Still another agitator has been devised that moves laterally relative to the device's fore-aft direction of operation, such as shown in U.S. Pat. No. 3,685,081. However, this device also suffers from notable shortcomings. for example, the two reciprocating brushes do not fully cover the surface being cleaned, and therefore are believed to provide inconsistent cleaning. Furthermore, the device is believed to cause accelerated wear of the surface being cleaned because the entire weight of the device rests on the agitator brushes, and the brushes sweep through a relatively large range of motion. This device also fails to provide any vacuuming capability, and appears to be very difficult to operate on carpeted floors or other surfaces that would tend to hold the brushes and cause the machine to move erratically.
Similar agitating devices have been employed with accessory tool devices and “power heads” that plug into the main body of a cleaning device to provide remote cleaning capability. These devices suffer from similar deficiencies.
Vacuum cleaning devices often benefit from using a flexible strip that contacts the surface being cleaned to focus the vacuumed air and physically constrain the debris being recovered and direct it through the device's vacuum inlet nozzle. Such flexible strips are typically referred to as “wipers” or “squeegees.” Wipers are particularly effective when the device is used to clean bare floors, windows, or other hard surfaces that form a solid lower barrier that works in conjunction with the flexible strip to prevent debris from escaping the vacuum inlet nozzle. Wipers are also particularly useful with devices that are intended to recover fluids from the surface being cleaned, such as wet extractors and window washers, which deposit cleaning fluid on the surface then recover the fluid with a vacuum. These wipers can be used with both floor cleaning devices and hand-held cleaners, such as accessory cleaning tools and portable cleaners. While many designs for such wipers have been illustrated in the prior art, there still remains a need to provide an improved squeegee system that provides acceptable cleaning performance, but can be selectively removed from a cleaning device in a convenient manner.
Therefore, the objectives of the present invention are to provide various floor cleaning devices and features that partially or fully overcome or ameliorate these and various other shortcomings of the prior art. Although certain deficiencies in the related art are described in this background discussion and elsewhere, it will be understood that these deficiencies were not necessarily heretofore recognized or known as deficiencies. Furthermore, it will be understood that, to the extent that one or more of the deficiencies described herein may be found in an embodiment of the claimed invention, the presence of such deficiencies does not detract from the novelty or non-obviousness of the invention or remove the embodiment from the scope of the claimed invention.